Cycloid transmission with an adjustable ring

ABSTRACT

Examples are provided that describe a cycloid transmission with an adjustable ring. An example cycloid transmission includes a disc and a motor shaft attached to the disc. The motor shaft is capable of rotating the disc around an outer ring of rollers. The outer ring of rollers surrounds the disc. As the disc is rotated, contact is made between the disc and the outer ring of rollers. A cycloid transmission also comprises an adjustable ring that is interposed between the motor shaft and the disc. A circumference of the adjustable ring can be adjusted in order to cause expansion of a radius of the disc. This expansion will result in increased contact of the disc with the outer ring of rollers and thereby lower backlash during rotation of the disc.

CROSS REFERENCE TO RELATED APPLICATION

The present disclosure is a divisional patent application of and claimspriority to U.S. patent application Ser. No. 14/275,984, filed on May13, 2014, the entire contents of which are herein incorporated byreference.

BACKGROUND

Unless otherwise indicated herein, the materials described in thissection are not prior art to the claims in this application and are notadmitted to be prior art by inclusion in this section.

Use of electric motor actuators in a wide array of engineering designcan be attributed to the ease of introducing motion and the need forpreventing motion as required by a mechanism or system. An ability ofactuators to enable control without the use of oil has also madeactuators a popular choice in various implementations. Electric motoractuators for robotic and automation systems often require atransmission (speed reducer) in order to operate within speed-torquerequirements of a specific application and of the motor.

As an example, an electric linear actuator may exhibit a high speed andfast response that is useful when high acceleration and an ability tobrake quickly are needed. However, linear actuators tend to have a highcost, require a cooling option based on heat generated, and are limitedby a length associated with a given application. As another example, astepper motor has a capability to be highly reliable but withdiminishing torque as a speed of the motor is increased. There continuesto be a vast majority of robotic and automation systems being developedwith the aid of electric motors that are capable of performing arotational motion.

SUMMARY

In one example, a cycloid transmission is provided that comprises a discand a motor shaft attached to the disc. The motor shaft is capable ofrotating the disc. The cycloid transmission also comprises an outer ringof rollers that surrounds the disc. The outer ring of rollers contactsthe disc as the disc rotates. The cycloid transmission also comprises anadjustable ring that is interposed between the motor shaft and the disc.A circumference of the adjustable ring can be adjusted in order to causean expansion of a radius of the disc. The expansion of the radius of thedisc will result in an increased contact of the disc to the outer ringof rollers and thereby lower backlash during rotation of the disc.

In another example, a cycloid transmission is provided that comprises adisc and a shaft attached to the disc. The disc includes a surface on anoutside perimeter of the disc. The shaft is capable of rotating thedisc. The cycloid transmission also comprises an outer ring of rollersthat surrounds the disc. The outer ring of rollers contacts the disc asthe disc rotates. The cycloid transmission also comprises a gap betweenthe surface and the outer ring of rollers. The cycloid transmission alsocomprises an adjustable ring that includes an internal pressurizedvolume. An adjustable fastener may be inserted into the internalpressurized volume. Insertion of the adjustable fastener causes anincrease in a pressure around a circumference of the adjustable ring.Based on an amount of insertion into the adjustable ring, the amount ofinsertion will cause expansion of a radius of the disc and decrease thegap between the surface and the outer ring of rollers. This will resultin increased contact of the disc to the outer ring of rollers.

In another example, a cycloid transmission is provided that comprises adisc and an outer ring of rollers. The outer ring of rollers surroundsthe disc and contacts the disc as the disc rotates. The cycloidtransmission also comprises a primary housing that encompasses the outerring of rollers. The cycloid transmission also comprises a secondaryhousing that encompasses the primary housing. The cycloid transmissionalso comprises an adjustable ring that is interposed between the primaryhousing and the secondary housing. The adjustable ring includes aninternal pressurized volume. The internal pressurized volume isadjustable around a circumference of the adjustable ring. Adjustment ofthe internal pressurized volume around the circumference of theadjustable ring will cause a compression to be applied along an outsideperimeter of the primary housing. The compression will further result inan increased contact of the disc to the outer ring of rollers.

These as well as other aspects, advantages, and alternatives, willbecome apparent to those of ordinary skill in the art by reading thefollowing detailed description, with reference where appropriate to theaccompanying figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A illustrates an exploded view of an example cycloid transmission.

FIG. 1B illustrates a top view of another example cycloid transmission.

FIG. 2 illustrates an example cycloid transmission with a plurality ofset screws.

FIG. 3A illustrates another example cycloid transmission.

FIG. 3B illustrates a portion of an example cycloid transmission.

FIG. 3C illustrates another portion of an example cycloid transmission.

FIG. 4 illustrates another example cycloid transmission.

FIG. 5 illustrates another example cycloid transmission.

FIG. 6 illustrates another example cycloid transmission.

FIGS. 7A-7C illustrate different operating stages associated with anexample cycloid transmission.

FIG. 8 illustrates an example robotic system.

DETAILED DESCRIPTION

The following detailed description describes various features andfunctions of the disclosed systems and methods with reference to theaccompanying figures. In the figures, similar symbols identify similarcomponents, unless context dictates otherwise. The illustrative systemand method embodiments described herein are not meant to be limiting. Itmay be readily understood that certain aspects of the disclosed systemsand methods can be arranged and combined in a wide variety of differentconfigurations, all of which are contemplated herein.

Examples described herein include subsystems that enable a robotic endeffector, including a cycloid transmission, to operate in a rotationalmanner for an extended period of time. The cycloid transmission mayinclude a motor shaft that is attached to a disc for the purpose ofrotating the disc. The disc may rotate around an outer ring of rollersthat may surround the disc and are used to contact the disc as the discrotates. An adjustable ring may be interposed between the motor shaftand the disc. The adjustable ring may have a circumference that can beadjusted. This adjustment in the circumference will permit a radialforce to cause an expansion of a radius of the disc. As a result of anincreased radius, the disc will have an increased contact to the outerring of rollers. Due to the increased contact, a backlash associatedwith a movement of the disc may be lowered during rotation of the disc.

Referring now to the figures, FIG. 1A illustrates an exploded view of anexample cycloid transmission 100. The cycloid transmission 100 comprisesa motor shaft 102 for rotating a disc 108. The cycloid transmission 100in FIG. 1A illustrates an adjustable ring 104 that is interposed betweenthe motor shaft 102 and the disc 108.

Within the cycloid transmission 100, the adjustable ring 104 may becoupled to or attached to the disc 108. The adjustable ring 104 includesa set screw 106 that is inserted through the disc 108 and into theadjustable ring 104. Although not shown in FIG. 1A, a plurality of setscrews can be inserted through the disc 108 and into the adjustable ring104.

The adjustable ring 104 may be pressurized with either a gas or a fluidthat will result in a pressure to be contained by the adjustable ring104. The pressure contained by the adjustable ring 104 can be adjustedbased on a position of the set screw 106 within the adjustable ring 104.As the position of the set screw 106 is adjusted through an applicationof an external rotational force, the pressure contained by theadjustable ring 104 may increase.

An outer ring of rollers 110 surrounds the disc 108. As the disc 108rotates around the outer ring of rollers 110, a wobble/planetarymovement will be reduced by a use of a plurality of output shaft rollers112. The plurality of output shaft rollers 112 are coupled to the disc108 and are inserted within positions 114 of the disc 108. Therespective positions 114 may be in the form of a circular opening with adiameter greater than a diameter of a given output shaft roller of theplurality of the output shaft rollers 112. Although in FIG. 1A theplurality of output shaft rollers 112 is shown to be six, in otherexamples, the number associated with the plurality of output shaftrollers 112 may be increased or decreased based on a specificapplication requirement.

As is shown in FIG. 1A, the disc 108 is surrounded by the outer ring ofrollers 110. The outer ring of rollers 110 contact the disc 108 as thedisc 108 is rotated by the motor shaft 102.

The disc 108 may also comprise a plurality of teeth 109 as is shown inFIG. 1A. A given surface of the plurality of teeth 109 may wear awayover a period of time due to a continuous contact between the pluralityof teeth 109 and the outer ring of rollers 110. A gradual lossassociated with an original shape of the plurality of teeth 109 maycause the cycloid transmission 100 to experience a backlash.

The cycloid transmission 100 may also experience backlash due to poormanufacturing tolerances associated with various components of thecycloid transmission 100. In one example, the disc 108 may come from amanufacturer with poor quality assurance associated with themanufacturing of a plurality of discs. In one example, a given disc fromthe plurality of discs could fail to engage properly with the outer ringof rollers 110 based on a smaller radius of the given disc from theplurality of discs due to poor manufacturing. The given disc from theplurality of discs could then cause the cycloid transmission 100 toexperience a backlash.

In one example, as the motor shaft 102 rotates under normal operation, aheat that is generated based on a rotational movement may reach othercomponents of the cycloid transmission 100. The heat may spread to theadjustable ring 104 based on the adjustable ring 104 being coupled tothe motor shaft 102. The fluid within the adjustable ring 104 may becomprised of a silicone fluid that exhibits an increased viscosity whenheated. An increase in a thickness of the fluid may further causeadjustment of a circumference of the adjustable ring 104. As thepressure contained by the adjustable ring 104 is adjusted, the pressuremay cause an expansion of the radius of the disc 108 resulting inincreased contact of the disc 108 to the outer ring of rollers 110.

Within examples, an increase in the pressure of the gas or fluid withinthe adjustable ring 104 may occur by adjustment of the set screw 106.The pressure contained by the adjustable ring 104 will increase if thereis less of a volume available for the gas or fluid to occupy. In oneexample, the disc 108 may contain an opening that provides access to aplanar surface of the set screw 106. By applying a rotational force tothe planar surface of the set screw 106, the set screw 106 will occupymore of the volume available for the gas or fluid. With less volumeavailable for the gas or fluid, the pressure contained by the adjustablering 104 may be adjusted to cause an expansion of the radius of the disc108.

In one example, a plurality of set screws may also be used in place ofjust the set screw 106 to cause an increase in the pressure contained bythe adjustable ring 104. In one example, the plurality of set screws maybe spaced equidistantly apart from each other. Adjusting the pluralityof set screws will permit an increase contained by the adjustable ring104 to be applied from each of the plurality of set screws.

FIG. 1B illustrates a top view of the cycloid transmission 100. In oneexample, the adjustable ring 104 may be integrated with the disc 108 asis shown in FIG. 1B. A channel 107 within the disc 108 may provideaccess to the set screw 106. The channel 107 may allow adjustment of theset screw 106 and thereby cause an expansion of the radius of the disc108.

The adjustable ring 104 is not limited to use in the cycloidtransmission 100. There are many other gear trains that may experiencebacklash. Other gear trains would thereby benefit from the adjustablering. Gear trains that comprise spur gears, bevel gears, and worm gearsare just a few examples that may benefit in having a radius of a gearexpanded through the use of the adjustable ring in order to improvecontact between a plurality of gears.

FIG. 2 illustrates an example cycloid transmission 200. A top view ofthe cycloid transmission 200 is shown in FIG. 2. The cycloidtransmission 200 comprises a motor shaft 202 that is capable of rotatinga disc 208. An adjustable ring 204 is interposed between the motor shaft202 and the disc 208.

The disc 208 comprises a plurality of circular openings 218 and 220. Aplurality of output shaft rollers 210 and 211 are inserted through theplurality of circular openings 218 and 220. A diameter of a givencircular opening 218 from the plurality of circular openings 218 and 220is larger than a diameter of a given output shaft roller 210 from theplurality of output shaft rollers 210 and 211. This enables theplurality of output shaft rollers 210 and 211 to move around theplurality of circular openings 218 and 220 in order to stabilize arotational motion of the disc 208.

An outer ring of rollers 206 surrounds the disc 208 as shown in FIG. 2.The outer ring of rollers 206 contacts the disc 208 as the disc 208 isrotated by the motor shaft 202. A continuous contact may eventuallycause an outer edge 222 of the disc 208 to be worn away. Over a givenperiod of time, the disc 208 may no longer contact the outer ring ofrollers 206, to the same degree, based on the outer edge 222 of the disc208 having been worn away. This loss in contact may cause the cycloidtransmission 200 to experience a backlash (slippage) and not operate inan intended manner.

In one example, the adjustable ring 204 comprises a circumference 216that can be adjusted in order to cause expansion of a radius of the disc208. An expansion of the radius of the disc 208 may be achieved throughthe use of a plurality of set screws 212 and 214. The plurality of setscrews 212 and 214 may be spaced equidistantly apart from each other.The plurality of set screws 212 and 214 are inserted through the disc208 and into the adjustable ring 204. Adjusting a position of theplurality of set screws 212 and 214 within the adjustable ring 204 willcause an adjustment of a pressure of a fluid. If the adjustment causesan increase in the pressure of the fluid, then that will cause expansionof the radius of the disc 208. Expanding the radius of the disc 208 willbring the outer edge 222 of the disc 208 in closer proximity with theouter ring of rollers 206 and lower backlash during rotation of the disc208.

FIG. 3A illustrates another example cycloid transmission 300. A top viewof the cycloid transmission 300 is shown. The cycloid transmission 300comprises a shaft 302 attached to a disc 306. The shaft 302 is capableof rotating the disc 306. An outer ring of rollers 310 surrounds thedisc 306. The outer ring of rollers 310 contacts the disc 306 as thedisc 306 is rotated by the shaft 302.

The disc 306 includes a surface 308 on an outside perimeter 309 of thedisc 306 that makes contact with the outer ring of rollers 310 as thedisc 306 is rotated. The disc 306 also includes a plurality of circularopenings 324 and 326 that are configured to receive a plurality ofoutput shaft rollers 320 and 322. In one example, the disc 306 mayinclude a plurality of teeth 307 and 305 along the outside perimeter 309for interfacing with the outer ring of rollers 310.

A gap 312 exists between the surface 308 and the outer ring of rollers310. While the disc 306 is rotated around the outer ring of rollers 310,the gap 312 is decreased as the surface 308 makes contact with the outerring of rollers 310.

The cycloid transmission 300 as shown in FIG. 3A includes an adjustablering 304. In this example, the adjustable ring 304 is interposed betweenthe shaft 302 and the disc 306. The adjustable ring 304 includes aninternal pressurized volume 314. The internal pressurized volume 314 mayinclude fluid.

In one example, the adjustable ring 304 is sealed for a high pressure inorder to permit an even radial force to be applied in all directionsfrom the internal pressurized volume 314.

In one example, the adjustable ring 304 may be manufactured in a splitmanner as a first and second part. A portion of the internal pressurizedvolume 314 may be machined into the first and second part. In oneexample, the first and second part could be manufactured out ofaluminum, steel, and stainless steel. The first and second part couldthen be welded back together. In one example, the first and second partcould also be bolted together with a gasket seal.

An adjustable fastener 316 is shown to be inserted into the internalpressurized volume 314. Inserting the adjustable fastener 316 into theinternal pressurized volume 314 may cause an increase in a pressure ofthe internal pressurized volume 314 around a circumference 318 of theadjustable ring 304. The increase in the pressure of the internalpressurized volume 314 will cause an expansion of a radius of the disc306 and thereby decrease the gap 312 between the surface 308 and theouter ring of rollers 310. With an expansion of a radius of the disc306, there will be increased contact between the disc 306 and the outerring of rollers 310 as the disc 306 is rotated. The increased contactwill lower backlash in order to improve the performance of the cycloidtransmission 300.

FIG. 3B shows an exploded view of subcomponents of the cycloidtransmission 300. In one example the adjustable fastener 316 maycomprise a set screw 315 as is shown in FIG. 3B. Adjusting the set screw315 will serve to adjust the pressure of the internal pressurized volume314. The adjustable fastener 316 may also comprise any threaded fastenerthat permits adjustment of a position of the adjustable fastener 316within the internal pressurized volume 314.

Referring to FIG. 3B, in one example the adjustable ring 304 maycomprise an annular body having a top circular base 311 and a bottomcircular base 317. In an example, the set screw 315 may be inserted intothe adjustable ring 304 through the top circular base 311.

FIG. 3C shows an exploded view of subcomponents of the cycloidtransmission 300. In one example referring to FIG. 3C, a plurality ofset screws 315 and 319 may be inserted into the adjustable ring 304through the top circular base 311.

FIG. 4 illustrates another example cycloid transmission 400. A top viewof the cycloid transmission 400 is shown in FIG. 4. The cycloidtransmission 400 comprises a shaft 402 attached to a disc 404. The shaft402 is capable of rotating the disc 404. An outer ring of rollers 408surround the disc 404. As the disc 404 rotates, the outer ring ofrollers 408 will make contact with the disc 404.

As is shown in FIG. 4, the disc includes a plurality of circularopenings 410 and 412 configured to receive a plurality of output shaftrollers 414 and 416.

Referring to FIG. 4, a gear 406 for connecting with the outer ring ofrollers 408 is shown. The gear 406 may include a plurality of teeth 407for connecting with the outer ring of rollers 408. Over a period oftime, the plurality of teeth 407 may wear away due to continuous contactwith the outer ring of rollers 408. This may result in the cycloidtransmission 400 to experience a backlash.

The cycloid transmission 400 comprises an adjustable ring 409. Theadjustable ring 409 includes an internal pressurized volume 411. Theadjustable ring 409 may be interposed between the gear 406 and the disc404.

An adjustable fastener 418 is inserted into the internal pressurizedvolume 411. The insertion of the adjustable fastener 418 will cause anincrease in a pressure around a circumference 420 of the adjustable ring409. The pressure around the circumference 420 will cause an expansionof a radius of the disc 404 which will push the gear 406 into closerproximity with the outer ring of rollers 408.

FIG. 5 refers to an example cycloid transmission 500. A top view of thecycloid transmission 500 is shown in FIG. 5. The cycloid transmission500 comprises a disc 502 that is surrounded by an outer ring of rollers504. The outer ring of rollers 504 makes contact with the disc 502 asthe disc 502 rotates.

The outer ring of rollers 504 may comprise any given number of rollersbased on a specification pertaining to the disc 502.

In one example, a primary housing 506 encompasses the outer ring ofrollers 504. A secondary housing 508 encompasses the primary housing506. An adjustable ring 510 is interposed between the primary housing506 and the secondary housing 508.

The adjustable ring 510 includes an internal pressurized volume 512 thatis adjustable around a circumference 514 of the adjustable ring 510. Inone example, the internal pressurized volume 512 is filled with a fluid.Adjusting the internal pressurized volume 512 may cause a compression tobe applied along an outside perimeter 516 of the primary housing 506.The compression will result in increased contact of the disc 502 to theouter ring of rollers 504 by forcing the outer ring of rollers 504 to bein a closer proximity to the disc 502.

Referring to FIG. 5, a set screw 518 is inserted through the primaryhousing 506 and into the adjustable ring 510. By applying a rotationalforce and thereby adjusting the set screw 518, there may be an increasein a pressure of the internal pressurized volume 512.

In one example, a plurality of set of screws 518 and 519 are insertedthrough the primary housing 506 and into the adjustable ring 510 asshown in FIG. 5. A given set screw of the plurality of set screws 518and 519 can be adjusted in order to cause an increase in the pressure ofthe internal pressurized volume 512. The plurality of set screws 518 and519 may be positioned along the circumference 514 of the adjustable ring510 in order to increase the pressure of the internal pressurized volume512 from a number of positions along the circumference 514 of theadjustable ring 510.

The secondary housing 508 may include a material with a higher hardnessthan what a different material that comprises the primary housing 506.The material of the secondary housing 508 may include a metal or anyother solid. This will ensure that the secondary housing 508 is notaffected by the increase in the pressure of the internal pressurizedvolume 512.

The primary housing 506 may be comprised of a solid that is less firmthan the secondary housing. In one example, a synthetic material madefrom a wide range of organic polymers may be used. The syntheticmaterial to be used in the primary housing 506 may exhibit a slightlyelastic form based on the increase in the pressure of the internalpressurized volume 512 which will enable the outer ring of rollers 504to be positioned closer to the disc 502.

FIG. 6 refers to another example cycloid transmission 600. A top view ofthe cycloid transmission 600 is shown in FIG. 6. The cycloidtransmission 600 comprises a disc 602 that is surrounded by an outerring of rollers 604. The outer ring of rollers 604 makes contact withthe disc 602 as the disc 602 rotates.

In one example, a primary housing 606 encompasses the outer ring ofrollers 604. A secondary housing 608 encompasses the primary housing606. An adjustable ring 610 is interposed between the primary housing606 and the secondary housing 608.

The adjustable ring 610 includes an internal pressurized volume 612 thatis adjustable around a circumference 614 of the adjustable ring 610.Adjusting the internal pressurized volume 612 may cause a compression tobe applied along an outside perimeter 616 of the primary housing 606.The compression will result in increased contact of the disc 602 to theouter ring of rollers 604.

In one example, the internal pressurized volume 612 may be adjusted by avalve 618 coupled to the secondary housing. Referring to FIG. 6, thevalve 618 may be accessed from the exterior 620 of secondary housing.This could enable a pressure of the internal pressurized volume 612 tobe adjusted without the need to disassemble a component associated withthe cycloid transmission 600.

FIGS. 7A-7C illustrate three different stages pertaining to an operationof a cycloid transmission 700. Referring to FIG. 7A, the cycloidtransmission 700 comprises a shaft 702 for rotating a disc 706. Anadjustable ring 704 is interposed between the disc 706 and the shaft702. The disc 706 rotates around an outer ring of rollers 708.

In one example, the disc 706 is about to make contact with a givenroller of the outer ring of rollers 708 at position 710 during theoperation of the cycloid transmission 700 as is shown in FIG. 7A. Theproximity of the disc 706 to the outer ring of rollers 708 at a givenposition 710 permits the cycloid transmission 700 to perform asintended.

Referring to FIG. 7B, the cycloid transmission 700 is shown to operatewhile exhibiting a backlash. The backlash may be caused as a surface 716of the disc 706 begins to wear away based on continuous contact with theouter ring of rollers 708.

In one example, at a given position 712 it can be seen that disc 706 nolonger engages with the outer ring of rollers 708 as is shown in FIG.7B. This may cause the cycloid transmission 700 to exhibit an unintendedoperating behavior due to backlash.

Referring to FIG. 7C, the cycloid transmission 700 is shown to operatewith a lowered backlash. In one example, this may be achieved byadjusting a circumference 720 of the adjustable ring 704. Thecircumference 720 of the adjustable ring 704 may be adjusted byincreasing a pressure contained by an internal pressurized volume of theadjustable ring 704.

As the circumference 720 of the adjustable ring 704 is adjusted, aradius of the disc 706 will increase. This will bring the disc 706 incloser proximity to the outer ring of rollers 708 such as at a givenposition 714. With an increased radius, the disc 706 will be able toengage with the outer ring of rollers 706 and the cycloid transmission700 will perform as originally intended.

FIG. 8 shows an example robotic system 800 where a cycloid transmission802 may be implemented in order to assist with a rotational movement.The robotic system includes an end effector 806 that is used to interactwithin an environment.

A latch 804 is shown that permits access to the cycloid transmission 802as is shown in FIG. 8. The ability to access the cycloid transmission802 by use of the latch 804 will permit an adjustable ring of thecycloid transmission 802 to be adjusted.

The adjustable ring of the cycloid transmission 802 may be adjusted whenthe robotic system starts to exhibit a backlash associated with amovement of the end effector 806. In one example, the adjustable ringmay be adjusted through the use of a fastener. The fastener may comprisea set screw or a plurality of set screws. In one example the adjustablering may be adjusted through the use of a valve.

After the adjustable ring has been adjusted, the cycloid transmission802 may have a lowered backlash and thereby allow for an intendedoperation of the robotic system 800. This will in turn permit the endeffector 806 to be used in an effective manner.

It should be understood that arrangements described herein are forpurposes of example only. As such, those skilled in the art willappreciate that other arrangements and other elements (e.g. machines,interfaces, functions, orders, and groupings of functions, etc.) can beused instead, and some elements may be omitted altogether according tothe desired results. Further, many of the elements that are describedare functional entities that may be implemented as discrete ordistributed components or in conjunction with other components, in anysuitable combination and location, or other structural elementsdescribed as independent structures may be combined.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopebeing indicated by the following claims, along with the full scope ofequivalents to which such claims are entitled. It is also to beunderstood that the terminology used herein is for the purpose ofdescribing particular embodiments only, and is not intended to belimiting.

What is claimed is:
 1. A cycloid transmission comprising: a disc; anouter ring of rollers surrounding the disc and contacting the disc asthe disc rotates; a primary housing that encompasses the outer ring ofrollers; a secondary housing that encompasses the primary housing; andan adjustable ring interposed between the primary housing and thesecondary housing, wherein the adjustable ring includes an internalpressurized volume and the internal pressurized volume is adjustablearound a circumference of the adjustable ring to cause a compressionapplied along an outside perimeter of the primary housing resulting inincreased contact of the disc to the outer ring of rollers.
 2. Thecycloid transmission of claim 1, wherein the internal pressurized volumeis adjustable around the circumference of the adjustable ring to causethe compression to increase contact of the disc to the outer ring ofrollers by forcing the outer ring of rollers to be in a closer proximityto the disc.
 3. The cycloid transmission of claim 1, further comprisinga set screw inserted through the primary housing and into the adjustablering, wherein adjustment of the set screw causes adjustment of theinternal pressurized volume.
 4. The cycloid transmission of claim 1,further comprising a plurality of set screws inserted through theprimary housing and into the adjustable ring, wherein adjustment of theplurality of set screws cause adjustment of the internal pressurizedvolume.
 5. The cycloid transmission of claim 4, wherein the plurality ofset screws are positioned along the circumference of the adjustablering.
 6. The cycloid transmission of claim 4, wherein the plurality ofset screws are positioned along the circumference of the adjustable ringto increase a pressure of the internal pressurized volume from a numberof positions along the circumference of the adjustable ring.
 7. Thecycloid transmission of claim 1, wherein the internal pressurized volumeincludes a fluid.
 8. The cycloid transmission of claim 1, furthercomprising a valve coupled to the secondary housing, wherein the valveis configured to adjust the internal pressurized volume.
 9. The cycloidtransmission of claim 8, wherein the valve is accessible from anexterior of the secondary housing.
 10. The cycloid transmission of claim1, wherein the secondary housing includes a material with a higherhardness than a material of the primary housing.
 11. The cycloidtransmission of claim 1, wherein the secondary housing includes a metalmaterial.
 12. The cycloid transmission of claim 1, wherein the primaryhousing comprises a material that is less firm than a material of thesecondary housing.
 13. The cycloid transmission of claim 1, wherein theprimary housing includes a synthetic material that exhibits an elasticform based on an increase in pressure of the internal pressurizedvolume.
 14. A cycloid transmission comprising: a disc; an outer ring ofrollers surrounding the disc and contacting the disc as the discrotates; a primary housing that encompasses the outer ring of rollers; asecondary housing that encompasses the primary housing; an adjustablering interposed between the primary housing and the secondary housing,wherein the adjustable ring includes an internal pressurized volume; anda set screw inserted through the primary housing and into the adjustablering, wherein adjustment of the set screw causes adjustment of theinternal pressurized volume of the adjustable ring forcing the outerring of rollers to be in a closer proximity to the disc.
 15. The cycloidtransmission of claim 14, further comprising a plurality of set screwsinserted through the primary housing and into the adjustable ring,wherein adjustment of the plurality of set screws cause adjustment ofthe internal pressurized volume.
 16. The cycloid transmission of claim15, wherein the plurality of set screws are positioned along acircumference of the adjustable ring.
 17. The cycloid transmission ofclaim 15, wherein the plurality of set screws are positioned along acircumference of the adjustable ring to increase a pressure of theinternal pressurized volume from a number of positions along thecircumference of the adjustable ring.
 18. The cycloid transmission ofclaim 14, wherein the internal pressurized volume includes a fluid. 19.The cycloid transmission of claim 14, further comprising a valve coupledto the secondary housing, wherein the valve is configured to adjust theinternal pressurized volume.
 20. The cycloid transmission of claim 19,wherein the valve is accessible from an exterior of the secondaryhousing.